Chiral Assemblies of Achiral Rigid-Flexible Molecules at the Air/Water Interface Induced by Silver(I) Coordination

Chiral films are obtained from achiral rigid-flexible molecules. Due to hydrogen bonding and steric constraints, these molecules can self-assemble into chiral assemblies at the air/water interface upon compression. When the molecules are spread on a subphase containing AgNO3, they form a stable monolayer through coordination with AgI ions, as confirmed by surface pressure–area isotherms, UV/Vis and FTIR spectroscopy, and AFM. More interestingly, macroscopic chirality was detected in the AgI-coordinated films by circular dichroism measurements. The formation mechanisms of the two kinds of chiral films are briefly discussed.